It is known to recycle items such as glass and plastic bottles. This helps conserve resources and energy. While the return of empty bottles was previously mostly a manual process, more automated methods of receiving empty bottles have been developed.
One such device for receiving empty water bottles is disclosed in U.S. Patent Publication US2007/0012541 A1 which is incorporated herein by reference. The device and method disclosed in the publication provides for a bottle collection bin that receives and securely stores numerous empty bottles until such time as the bin is emptied. The bin includes a receiving chute through which the bottles are moved from the exterior into the interior of the bin where the bottles are stored. The bin can include means for detecting the intake of a bottle, such as a sensor, and means for indicating that a bottle was received, such as by dispensing a receipt (e.g. ticket), as proof that a bottle was returned. The receipt, for example, could be used to obtain a discount for the purchase of another full water bottle, or for the return of a deposit on the bottle.
In one known device, the means for sensing the return of the bottle is provided by an optical sensor placed near an outlet of the bottle receiving chute. The chute has an inlet through which the bottle is placed into the bin, and an outlet through which the bottle falls into the locked bin cage from where it can be removed only by an authorized person. As a bottle is pushed through the inlet of the bottle receiving chute towards the outlet, the bottle eventually exits from the outlet and falls into the cage, passing by the optical sensor that detects the bottle. Placement of the sensor near the outlet of the chute allows the sensor to detect bottles that have exited the chute and are falling into the cage. Since many such bins may be placed in areas that are not monitored, it is important to provide adequate security and sensing means so that only one receipt is dispensed for each empty bottle, regardless of attempts by users to fool the device into issuing additional receipts. Nevertheless, one concern with presently known systems is that users can tamper with the device by moving a bottle or other item through the chute and, rather then releasing the item, move the item back and forth across the sensor to obtain unauthorized tickets or receipts. Another major concern is the possibility of false sensor detections. For example, it has been found that lightning, birds flying near the sensor, or even objects blown by the wind past the sensors can trigger false detection signals. Accordingly, an improved bottle receiving device that can securely receive bottles and which is less prone to tampering and false signals would be advantageous.